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to MCU. Without start signal from MCU, RHT03 will not give response signal to MCU. One start signal for one

response data from RHT03 that reflect the relative humidity and temperature. RHT03 will change to standby status

when data collecting finished if it don't receive start signal from MCU again.

See below figure for overall communication process, the interval of whole process must beyond 2 seconds.

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1) Step 1: MCU send out start signal to RHT03 and RHT03 send response signal to MCU

Data-bus's free status is high voltage level. When communication between MCU and RHT03 begins, MCU will

pull low data-bus and this process must beyond at least 1~10ms to ensure RHT03 could detect MCU's signal, then

MCU will pulls up and wait 20-40us for RHT03's response.

When RHT03 detect the start signal, RHT03 will pull low the bus 80us as response signal, then RHT03 pulls up

80us for preparation to send data. See below figure:

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